Fix for issue #4460

Author: Matt Casters

plugins/transforms/javascript/src/main/java/org/apache/hop/pipeline/transforms/javascript/ScriptValuesAddedFunctions.java

@@ -142,6 +142,7 @@ public class ScriptValuesAddedFunctions extends ScriptableObject {
     "trim",
     "substr",
     "getVariable",
+    "resolveVariable",
     "setVariable",
     "LuhnCheck",
     "getDigitsOnly",
@@ -2000,6 +2001,35 @@ public static String getVariable(
     return sRC;
   }
 
+  public static String resolveVariable(
+      Context actualContext, Scriptable actualObject, Object[] argList, Function functionContext) {
+    String sRC = "";
+    String sArg1 = "";
+    if (argList.length == 1) {
+      try {
+        Object scmo = actualObject.get(CONST_TRANSFORM, actualObject);
+        Object scmO = Context.jsToJava(scmo, ITransform.class);
+
+        if (scmO instanceof ITransform) {
+          ITransform scm = (ITransform) Context.jsToJava(scmO, ITransform.class);
+
+          sArg1 = Context.toString(argList[0]);
+          return scm.resolve(sArg1);
+        } else {
+          // running via the Test button in a dialog
+          sArg1 = Context.toString(argList[0]);
+          return sArg1;
+        }
+      } catch (Exception e) {
+        sRC = "";
+      }
+    } else {
+      throw Context.reportRuntimeError(
+          "The function call resolveVariable accepts a single argument.");
+    }
+    return sRC;
+  }
+
   // Return the output row metadata
   public static IRowMeta getOutputRowMeta(
       Context actualContext, Scriptable actualObject, Object[] argList, Function functionContext) {

plugins/transforms/javascript/src/main/resources/org/apache/hop/pipeline/transforms/javascript/jsFunctionHelp.xml

@@ -1248,6 +1248,25 @@
         </Arguments>
     </jsFunction>
 
+    <jsFunction name="resolveVariable">
+        <help>Resolves a variable expression.</help>
+        <sample>// Converts the given variable expression into its underlying value.
+            //
+            // Usage:
+            // resolveVariable(var);
+            // 1: String - The variable expression to resolve.
+            //
+            // 2025-01-27
+            //
+            var strVarName="${PROJECT_HOME}/output/";
+            Alert(resolveVariable(strVarName));
+        </sample>
+        <type>4</type>
+        <Arguments>
+            <argument id="1">var</argument>
+        </Arguments>
+    </jsFunction>
+
     <jsFunction name="LuhnCheck">
         <help>Check if the given Value is a valid Card Number using the Luhn algorithm.</help>
         <sample>// Returns true, if the given value is a valid card number